JPH02100028A - Automatic stroboscopic device - Google Patents

Abstract

PURPOSE:To accurately control the light emission of plural flash discharge tubes without using any commutating circuit by turning on and off a transistor(TR) whose main electrode is connected at one end to respective cathodes of plural flash discharge tubes and grounded at the other end. CONSTITUTION:The supply of an on signal from a TR driving circuit 9 to the control electrode of the TR 3 is controlled to control the light emission of the flash discharge tubes 1 and 2, one by one. Further, the output period of a light emission signal outputted from a light emission signal generating circuit 16 is controlled to set the quantity of light emission itself. Consequently, light emitting operation can be controlled without using any communicating circuit and further the output period of the light emission signal can easily be determined according to the charging voltage, etc., of, for example, a main capacitor 5 to accurately control the quantity of light emission.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a strobe device used as an auxiliary light source during photography, and more particularly to an autostroboscopic device equipped with a plurality of flash discharge tubes, each of which can control the amount of light emitted.

BACKGROUND OF THE INVENTION A typical conventional autostroboscopic device is one in which one of two flash discharge tubes is used for bounce light and the other is used for light from the front of the subject (for example: Japanese Patent Publication No. 56-94339.

No. 56-128928, etc.). In addition, there are also widely known devices that perform preliminary light emission and control the main light emission operation (for example, Japanese Patent Laid-Open No. 185735/1983).

Looking at the method of controlling the amount of light emitted by such an auto strobe device, the former device uses the light emitted from two discharge tubes directly for photographing, so usually each of these discharge tubes is connected in series with a cyrisk. The amount of light emitted from each discharge tube is controlled by connecting the thyristor and controlling the operation of this thyristor using a well-known commutation circuit or the like. On the other hand, in the latter device, the amount of light emitted from the flash discharge tube for main light emission is controlled using a thyristor and its commutation circuit, and the amount of light emitted from the flash discharge tube for pre-flash is controlled by the main capacitor for pre-flash. It is controlled by making the capacity variable.

Problems to be Solved by the Invention By the way, looking at the configuration of the above-mentioned device itself,
Both require commutation circuits.

The necessity of a commutation circuit means that the next control operation can be performed only after the commutation capacitor has been fully charged, and it is not possible to repeatedly perform light emitting operations in a very short period of time.

Furthermore, the latter device requires a plurality of main capacitors for secondary light emission, changeover switches, etc., which increases the cost and increases the size. In addition, since the amount of light emitted is controlled by switching the main capacitor, there is a possibility that the amount of light emitted may vary due to variations in the charging voltage of the main capacitor.

The present invention has been made in consideration of the above points, and an object of the present invention is to provide an autostroboscopic device that can accurately control the light emission of a plurality of flash discharge tubes without using a commutation circuit. do.

Means for Solving the Problems An autostroboscopic device according to the present invention includes a plurality of flash discharge tubes, one main pole being connected to the cathode of the flash discharge tubes,
a transistor whose other main pole is connected to ground;
A main capacitor that supplies luminous energy to each of the flash discharge tubes via a transistor, a transistor drive circuit that is connected to the control pole of the transistor and outputs an on signal to make the transistor conductive when activated, and a flash discharge tube. A light emission signal generation circuit that generates and outputs a plurality of light emission signals corresponding to each tube based on various information such as the charging voltage of the main capacitor, and operates only when one of the plurality of light emission signals is supplied. At least an operation control circuit that outputs a control signal for operating the transistor drive circuit and makes the transistor conductive is provided corresponding to each of the flash discharge tubes, and the light emission signal is supplied directly or via the operation control circuit. It is equipped with a trigger circuit that activates only the corresponding flash discharge tube.

Function: Since the autostroboscopic device according to the present invention has the above-described configuration, by controlling the supply of the ON signal from the transistor drive circuit to the control pole of the transistor, the light emission of the plurality of flash discharge tubes can be made independent of each other. controlled by Furthermore, the amount of light emission itself is set by controlling the output period of the light emission signal output from the light emission signal generation circuit.

Therefore, the light emission operation can be controlled without using a commutation circuit, and since it is extremely easy to determine the output period of the light emission signal according to the charging voltage of the main capacitor, for example, the amount of light emission can also be controlled accurately. be done.

Embodiments Hereinafter, embodiments of the auto strobe device of the present invention will be described.
This will be explained with reference to the drawings.

FIG. 1 is a circuit diagram showing the configuration of essential parts of a first embodiment of the present invention.

As shown in the figure, this embodiment includes two flash discharge tubes 1.2, and the cathodes of these discharge tubes 1, 2 are connected to one of the main poles of a transistor 3.

The other main pole of transistor 3 is connected to ground G. A connection body consisting of these two flash discharge tubes 1 and 2 and a transistor 3 is connected in series between both terminals of a main capacitor 50 with a parallel connection body 4 consisting of an inductor and a diode.

Note that this transistor 3 includes, for example, I, G, B, T (Insulated G), which has been put into practical use in recent years.
It goes without saying that ate BipolarTransistor) can be used.

The main capacitor 5 outputs a high DC voltage. It is charged by the power supply circuit 6.

A trigger circuit 7.8 is provided for each flash discharge tube 1.2, by means of which only the corresponding flash discharge tube is excited.

A transistor drive circuit 9 is connected to the control pole of the transistor 3. The transistor drive circuit 9 receives a control signal from an operation control circuit 10 (described later), generates an on signal for making the transistor 3 conductive, and supplies it to its control pole.

The operation control circuit 10 is a circuit that controls not only the operation of the transistor drive circuit 9 but also the trigger circuits 7 and 8,
It is composed of an OR circuit 11, gate circuits 12 and 13, and inverters 14 and 15. Gate circuits 12 and 13 become conductive when a high level signal is supplied from inverter 14 and 15, respectively.

This operation control circuit 10 includes a light emission signal generation circuit 1 which will be described later.
The light emission signal generated by 6 is input to the input terminal 10a.

10b, the operation of the transistor drive circuit 9 and the like is controlled.

The light emitting signal generation circuit 16 has, for example, a flash discharge tube 1, which is supplied from an input terminal group 16c to the light emitting signal generating circuit 16.
A light emission signal whose generation timing and generation period are controlled is output based on selection information as to which of 2 to be generated, information on the amount of light reflected from the subject, information on the charging voltage of the main capacitor, etc.

Next, the operation of this embodiment will be explained in FIG.
This will be explained with reference to the signal waveforms shown in FIG.

The main capacitor 5 is completely charged by the power supply circuit 6, and the light emission preparation state is reached, and the light emission signal generation circuit 16 outputs the signal at time t.
, based on various information supplied from the input terminal group 16c to the output terminal 16a, a light emission signal having a pulse width T as shown in FIG. 2(a) is output.

This light emission signal is supplied to the operation control circuit 10, and is supplied to the gate circuit 12 and the inverter 15 via its input terminal 10a. At this time, the output signal of the other output terminal 16b of the light emission signal generation circuit 16 is maintained at a low level as shown in FIG. 2('b), and at time 1. Leave it there,
The gate circuit 12 becomes conductive as shown in FIG. 2 (C1), and the gate circuit 13 becomes non-conductive as shown in FIG. 2 (di).

Therefore, the light emission signal is supplied to the OR circuit 11 and the trigger circuit 7 via the gate circuit 12.

When the OR circuit 11 is supplied with the light emission signal, the
As shown in FIG. 1, a control signal for operating the transistor drive circuit 9 is generated during the light emission signal output period T.

As a result, during the period T, the transistor drive circuit 9 generates an on signal for the transistor 3, making the transistor 3 conductive as shown in FIG. 2 (fl).

At the same time, the trigger circuit 7 also operates at the time t1 when the light emission signal is supplied, and excites the corresponding flash discharge tube 1.

As a result, the flash discharge tube 1 consumes the charge stored in the main capacitor 5 and emits light, as shown in FIG. 2 (tg).

The flash discharge tube 1 is mounted at a time t1 as shown in FIG.
At time t2 after a period T has elapsed, the output of the light emitting signal is stopped, the output of the OR circuit 11 becomes low level, the operation of the transistor drive circuit 9 is stopped, and the transistor 3 is returned to the on state. , ends the light emission.

Next, as shown in FIG. It is supplied from the terminal 10b to the gate circuit 13 and the inverter 14. As a result, contrary to the case where the previous light emission signal was output from the output terminal 16a, the signal shown in FIG.
As shown in C1, the gate circuit 12 of the operation control circuit 10
becomes non-conductive, and the gate circuit 13 becomes conductive as shown in the figure (dl).

Therefore, the light emission signal is supplied to the OR circuit 11 and the trigger circuit 8 through the gate circuit 13, and as shown in FIG. During this period, the transistor 3 is made conductive as shown in FIG. on the other hand,
The trigger circuit 8 triggers the corresponding flash discharge tube 2 at time t3.
excite. As a result, as shown in FIG. 2 +h+, the flash discharge tube 2 consumes the charge in the main capacitor 5 and emits light.

It is clear that the light emission of the flash discharge tube 2 also stops at the time t4 when the output of the light emission signal stops, after the period T1 has elapsed from the time t3, similarly to the light emission of the flash discharge tube 1 described above.

As described above, in this embodiment, the light emission signal generation circuit 16
The light emission and light emission control operation of the two flash discharge tubes 1.2 are controlled by the light emission signal outputted with the output timing and output period set based on various information. By setting various output states, the flash discharge tube 1.2 can be caused to emit light in a desired state.

Note that the output terminal 16a of the light emission signal generation circuit 16.

16b, the trigger circuits 7, 8 and The transistor drive circuit 9 does not operate, and neither of the flash discharge tubes 1 and 2 emits light. That is, the operation control circuit 10 in this embodiment has a function of preventing the two flash discharge tubes 1.2 from emitting light at the same time.

FIG. 3 is a circuit diagram of a main part of a second embodiment of an autostroboscopic device according to the present invention, in which the same reference numerals as in FIG. 1 indicate components having the same functions.

In this embodiment, as is clear from FIG. 3, two flash discharge tubes 1.2 are each arranged in a parallel body 4a.

4b to other main capacitors 5a and 5b, and the processing system for the light emission signal output from the light emission signal generation circuit 16 is different from the embodiment shown in FIG. That is, each light emission signal is directly transmitted to the trigger circuit 7.
, 8 as well as AND circuits 17,
The signal is supplied to an operation control means 10° consisting of a NAND circuit 18° and an OR circuit 19.

The operation of this embodiment will be explained below.

In the light emission preparation state where the main capacitors 5a, 5b, etc. are charged by the power supply circuit 6, the light emission signal generation circuit 16 is activated based on various information inputted to the input terminal group 16c.
outputs a light emission signal whose output timing and output period are controlled from the output terminal 16a, this light emission signal is directly supplied to the trigger circuit 7, and is also supplied to the N of the operation control circuit 10°.
It is also supplied to an AND circuit 18 and an OR circuit 19. The trigger circuit 7 operates based on the light emission signal and excites the corresponding flash discharge tube 1.

On the other hand, the other output terminal 16 of the light emission signal generation circuit 16
Since b is maintained at a low level, both the NAND circuit 18 and the OR circuit 19 output high level signals. As a result, the AND circuit 17 outputs a high level signal, operates the transistor drive circuit 9, and makes the transistor 3 conductive.

As a result, the flash discharge tube 1 consumes the charge in the main capacitor 5a and emits light.

The light emission from the flash discharge tube 1 is caused by the output of the light emission signal from the output terminal 16a being stopped, the output of the AND circuit 17 becomes a low level, the operation of the transistor drive circuit 9 is stopped, and the transistor 3 is turned off. It ends when it gets old.

Next, a case will be described in which a light emission signal based on various information is output from the output terminal 16b of the light emission signal generation circuit 16 in the light emission preparation state as described above.

The light emission signal from the output terminal 16b of the light emission signal generation circuit 16 is supplied to the trigger circuit 8, and is also supplied to the operation control circuit 1.
It is also supplied to the NAND circuit 18 and OR circuit 19 within 0°. Therefore, the trigger circuit 8 corresponds to the flash discharge tube 2.
excite. On the other hand, since the other output terminal 16a of the light emission signal generation circuit 16 is maintained at a low level, the NA
The ND circuit 18 and the OR circuit 19 each output a high level signal, and as in the previous case, the AND circuit 17 outputs a high level signal that becomes a control signal for the transistor drive circuit 9.
As a result, transistor 3 becomes conductive. Therefore, the flash discharge tube 2 consumes the charge in the main capacitor 5b and emits light, and the output of the light emission signal from the output terminal 16b stops, and the operation of the transistor drive circuit 9 stops. The process ends when the transistor 3 is turned off.

As described above, in the embodiment shown in FIG. 3, the light emission of the flash discharge tube 1.2 is selectively controlled by the light emission signal output from the light emission signal generation circuit 16 based on various information. The basic operation is the same as that of the embodiment shown in FIG. That is, although the main capacitors connected are different, the flash discharge tube 1 in the embodiment shown in FIG.
In the light emitting operation No. 2, various light emitting characteristics can be set by controlling the output timing and period of the light emitting signal based on various information, as in the embodiment shown in FIG.

Note that in the embodiment shown in FIG. 3, when the light emission signal is output from both the output terminals 16a and 16b of the light emission signal generation circuit 16, the output of the NAND circuit 18 becomes a low level, and the AND Transistor drive circuit 9 from circuit 17
control signal is not output. That is, the operation control circuit 1
Although the transistor 3 does not turn on due to the action of 0" and the trigger circuit 7°8 becomes operational, the flash discharge tubes 1 and 2
However, as in the previous embodiment shown in FIG. 1, no light is emitted.

Effects of the Invention In the autostroboscopic device according to the present invention, the plurality of flash discharge tubes are connected to each other by the on/off operation of a transistor whose main pole is connected to the cathode of each of the plurality of flash discharge tubes and the other end is connected to the ground. Since the light emitting operation of the LED is controlled, a commutation circuit is not required. Furthermore, the operation of the transistor drive circuit that controls the on/off operation of the transistor is controlled by the light emission signal output from the light emission signal generation circuit being supplied via the operation control circuit. , when multiple light emission signals are generated at the same time, there is no need to turn on the transistor in response to them, and furthermore, the operation timing and operation period also depend on the charging voltage of the main capacitor, the state of reflected light from the subject, etc. The output timing of the light emission signal, etc. is controlled based on various information, and can be easily and accurately controlled. As a result, the light emission operation of a plurality of flash discharge tubes can be realized independently and with various characteristics. can.

[Brief explanation of drawings]

1 is a circuit diagram of a main part of a first embodiment of an autostroboscopic device according to the present invention, FIG. 2 is a diagram for explaining the operation of the embodiment shown in FIG. The figure is a circuit diagram of a main part of a second embodiment of an autostroboscopic device according to the present invention. 1.2...Flash discharge tube, 3...Transistor, 4...・Parallel body, 5... Main capacitor, 6... Power supply circuit, 7, 8...
Trigger circuit, 9...transistor drive circuit,
10...Operation control circuit, 11...OR
Circuit, 12.13... Gate circuit 14.15.
...Inverter, 16...Light emission signal generation circuit, 17...AND circuit, 18...
NANDAND circuit...OR circuit. Name of agent: Patent attorney Shigetaka Awano and 1 other person +4-・-
Between f, family point pipe 3-1 rasist star 4--tν1 final 5-jL] chain J 6,-tji East negative-10--Issaku production c3 purchase 11--6- Profit 1, lj --- date E purchase diagram diagram

Claims (1)

[Claims] a plurality of flash discharge tubes; a transistor having one main pole connected to the cathode of the plurality of flash discharge tubes and the other main pole connected to ground; and the transistor for each of the plurality of flash discharge tubes. a main capacitor that supplies luminous energy through the transistor; a transistor drive circuit that is connected to the control pole of the transistor and outputs an on signal that makes the transistor conductive when activated; and a transistor drive circuit that corresponds to each of the plurality of flash discharge tubes. a light emission signal generation circuit that generates and outputs a plurality of light emission signals based on various information such as the charging voltage of the main capacitor; and a light emission signal generation circuit that operates only when one of the plurality of light emission signals is supplied; An operation control circuit that outputs a control signal for operating a transistor drive circuit to make the transistor conductive is provided corresponding to each of the plurality of flash discharge tubes, and the light emission signal is provided directly or directly to the operation control circuit. An autostroboscopic device comprising a trigger circuit which operates by being supplied through the flash discharge tube and which excites only the corresponding flash discharge tube.